Quantifying refractive error in companion dogs with and without nuclear sclerosis: 229 eyes from 118 dogs.

OBJECTIVE: To evaluate the relationship between nuclear sclerosis (NS) and refractive error in companion dogs. ANIMALS STUDIED: One hundred and eighteen companion dogs. PROCEDURES: Dogs were examined and found to be free of significant ocular abnormalities aside from NS. NS was graded from 0 (absent) to 3 (severe) using a scale developed by the investigators. Manual refraction was performed. The effect of NS grade on refractive error was measured using a linear mixed effects analysis adjusted for age. The proportion of eyes with >1.5 D myopia in each NS grade was evaluated using a chi-square test. Visual impairment score (VIS) was obtained for a subset of dogs and compared against age, refractive error, and NS grade. RESULTS: Age was strongly correlated with NS grade (p < .0001). Age-adjusted analysis of NS grade relative to refraction showed a mild but not statistically significant increase in myopia with increasing NS grade, with eyes with grade 3 NS averaging 0.58-0.88 D greater myopia than eyes without NS. However, the myopia of >1.5 D was documented in 4/58 (6.9%) eyes with grade 0 NS, 12/91 (13.2%) eyes with grade 1 NS, 13/57 (22.8%) eyes with grade 2 NS, and 7/23 (30.4%) eyes with grade 3 NS. Risk of myopia >1.5 D was significantly associated with increasing NS grade (p = .02). VIS was associated weakly with refractive error, moderately with age, and significantly with NS grade. CONCLUSIONS: NS is associated with visual deficits in some dogs but is only weakly associated with myopia. More work is needed to characterize vision in aging dogs.

Humeral intracondylar fissures and intracondylar sclerosis are common CT findings in the limb contralateral to a humeral condylar fracture in French bulldogs and spaniel breeds.

French bulldogs (FBD) are reported to be at an increased risk of developing humeral condylar fractures (HCF). Spaniel breeds have been reported to be at increased risk of HCF due to a high prevalence of humeral intracondylar fissures (HIF), which can predispose to fracture. The aims of this retrospective, single center, observational study were twofold. First, to compare the signalment, fracture configuration, and etiology of populations of FBD and spaniel breeds presenting with HCF at a single hospital. Second, to evaluate the computed tomographic (CT) findings of the contralateral elbow joints of FBD and spaniel breeds presenting with HCF for concomitant pathology. FBDs were overrepresented for HCF, most commonly presenting when skeletally immature, with a median age of 3.7 months. Fractures of the lateral condyle were the most common configuration for both breed groups. Sclerosis at the fracture site was identified in 62% of FBD and 95% of spaniels undergoing CT scans. Humeral intracondylar fissures and intracondylar sclerosis were commonly observed in the contralateral elbows of FBD (44% and 50%, respectively) and spaniel breeds (58% and 95%, respectively). Medial coronoid pathology, elbow incongruency, and periarticular osteophytes were not identified in the contralateral elbows of FBD but were identified in 29%, 4%, and 20% of spaniels, respectively. The high prevalence of HIF in the FBD group may be a predisposing factor for HCF in this breed.

Findings consistent with equine proximal suspensory desmitis can be reliably detected using computed tomography and differ between affected horses and controls.

The objective of this retrospective, observational, controlled study was to evaluate bone and soft tissue window CT images of the proximoplantar metatarsus III region in twenty horses with pain localized to the proximal suspensory ligament (PSL) and 20 horses with findings nonrelated to tarsal pain. All horses underwent CT and radiographic examination. Images were reviewed by three independent observers who graded the severity and localization of findings. Bone-related categories as well as soft tissue-related categories were evaluated. For the comparison of imaging findings in horses with and without proximal suspensory desmitis (PSD), mixed linear regression was performed. The intraclass correlation coefficient (ICC) was calculated to assess intraobserver agreement, and kappa statistics were employed to evaluate interobserver agreement. CT examination identified significantly more abnormalities in the diseased group. The scores for osseous exostosis (p = .015) and PSL enlargement (p = .004) were notably higher in PSD horses compared to controls. Intraobserver agreement was overall high (ICC .82-1.0), and interobserver agreement was substantial for the detection of mineralization (kappa = .61) and moderate for sclerosis (kappa = .43), exostosis (kappa = .43), and PSL enlargement (kappa = .48/.51). Measurements in the soft tissue window were significantly smaller than those in the bone window. Findings concurrent with PSD including osseous proliferation and sclerosis as well as soft tissue enlargement, mineralization, and avulsion can be reliably detected using CT. Findings from the current study supported the use of CT for evaluating horses with suspected PSD where high-field MRI is not available.

Lumbosacral endplate contour defect is frequently observed concurrent with other lumbosacral abnormalities on spinal CT of French Bulldogs.

Lumbosacral osteochondrosis has been previously described in large breed dogs with variable clinical signs. Its CT features are a contour defect at the dorsal aspect of either vertebral endplate, commonly with an adjacent fragment. Descriptions of this condition have not been previously published in an increasingly popular breed, French Bulldogs. Aims of this retrospective, descriptive, single center study were to evaluate CT lumbosacral abnormalities and the frequency of lumbosacral endplate contour defect in a large sample of French Bulldogs. The presence and location of lumbosacral endplate contour defect and the presence of a concurrent osseous fragment were recorded. Other abnormal CT findings such as L7-S1 disc herniation, cauda equina nerve roots compression or thickening, disc mineralization, endplate sclerosis, spondylosis deformans, S1 articular processes hypertrophy, transitional vertebrae, hemivertebrae, spina bifida, and block vertebrae were recorded. Lumbosacral CT abnormalities were present in 91.8% of dogs (168/183). The most common abnormality was an L7-S1 dorsal disc herniation (77.4%, 130/168). Among dogs with lumbosacral abnormalities, the frequency of a lumbosacral endplate contour defect was 47% (79/168). It mostly involved L7 (78.5%, 62/79) at its dorsolateral aspect (61.3%, 38/62). A mineralized fragment was identified in 62% of the defects (49/79). Endplate contour defects were most frequently seen with a concurrent disc herniation (93.7%, 74/79) causing nerve root compression in 63.3% (50/79) and with sclerosis (65.8%, 52/79). There was no definitive evidence of a relationship with clinical presentation in this sample of French Bulldogs; therefore, this finding should be interpreted with caution. The etiology remains unclear.

Hippocampal size did not differ between epileptic and non-epileptic dogs using volumetric and subjective methods.

Hippocampal changes in epilepsy may manifest as hippocampal atrophy/sclerosis. A recent human study suggests that the demonstration of hippocampal volume loss is more reliable using quantitative evaluation methods. The aim of the present study was to obtain volumetric data in both epileptic and healthy dogs, to compare hippocampal volumes in both groups, and to compare subjective and volumetric assessment. Volumetric measurements of the hippocampi, lateral ventricles and hemispheria were performed in 31 epileptic and 15 control dogs. There was a positive association between the body weight and the hemispheric volume, as well as between the hemispheric volume and the ipsilateral hippocampal volume. There was no significant correlation between age and the volume of any measured brain structures. There was no statistically significant difference between the hippocampal volumes of the control group and the epileptic group. A statistically significant difference between the two groups for hippocampus/hemispherium ratio or hippocampal asymmetric ratio was not identified. An extrapolated hippocampal volume based on body weight was not possible in this study population.

Multicentric B-cell lymphoma with presumed paraneoplastic generalized cutaneous sclerosis in a dog.

BACKGROUND: Reports of dermal sclerosis in dogs include scleroderma or morphea of unknown cause, cicatricial alopecia and congenital/hereditary fibrosis. CLINICAL SUMMARY: A 12-year-old, male castrated chihuahua-mix dog was evaluated for skin lesions of unknown duration. The dog had severe alopecia, skin thickening and marked peripheral lymphadenopathy. Lymph node cytological investigation, immunohistochemical investigation and clonality testing demonstrated an intermediate to large B-cell lymphoma. The thickened skin had severe collagen deposition, effacing adnexal structures. The dog's lymphoma was treated but the skin lesions remained unchanged. The dog was euthanized. CONCLUSIONS AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first report of multicentric B-cell lymphoma in a dog with concurrent diffuse cutaneous sclerosis, similar to a human paraneoplastic reaction.

Hippocampal necrosis and sclerosis in cats: A retrospective study of 35 cases.

Hippocampal necrosis and hippocampal sclerosis in cats is a neuropathological entity which is a major concern in feline epilepsy. The aim of our study was to identify associated pathologic brain lesions possibly serving as aetiological triggers in this condition. Therefore, the formalin-fixed and paraffin waxembedded brain tissue of 35 cats diagnosed with hippocampal necrosis or sclerosis was examined retrospectively. In 26 cats inflammatory infiltrates could be found in the hippocampus or adjacent brain regions. Fifteen out of these animals demonstrated mild to moderate infiltrations by lymphocytes and complement deposition in the hippocampus similar to human limbic encephalitis, seven showed unspecific, predominantly non-suppurative inflammation, and two demonstrated suppurative inflammation of the hippocampus or adjacent brain regions. Additionally, one cat was diagnosed with central nervous manifestation of feline infectious peritonitis virus and another one with cerebral Toxoplasma gondii infection. Intracranial neoplasia was present in five cases altogether. Three of them comprised meningioma which was present additionally to lesions resembling limbic encephalitis in two cases, and a dentate gyrus alteration in one case. The other two tumour-associated cases comprised oligodendroglioma. Structural alterations of the dentate gyrus together with hippocampal sclerosis were encountered in three cases in total. Besides the case associated with a meningioma, one case demonstrated lesions resembling limbic encephalitis. A vascular infarct in the temporal lobe was encountered in one cat. In four cases no lesions other than hippocampal necrosis or sclerosis were found. The involvement of feline immunodeficiency virus infections, which may be able to produce hippocampal lesions, was not encountered in the cats examined.

Bilateral Dentate Gyrus Structural Alterations in a Cat Associated With Hippocampal Sclerosis and Intraventricular Meningioma.

A 13-year-old cat had a history of seizures for 3 years that resembled temporal lobe epilepsy. Histologic examination of the brain revealed bilateral hippocampal alterations, including hypergyration and broadening of the dentate gyrus associated with hippocampal sclerosis and an intraventricular meningioma near the hippocampal region. The findings in the dentate gyrus were interpreted as a congenital malformation; however, it could not be ruled out that the alterations were induced by the seizures. Similar changes of the dentate gyrus have not been previously described in cats.

Feline gastrointestinal eosinophilic sclerosing fibroplasia associated with Candida albicans.

Feline gastrointestinal eosinophilic sclerosing fibroplasia (FGESF) is a rare and poorly understood disease characterised by the infiltration of eosinophils and the development of fibrous tissue within the gastrointestinal tract of cats. A 2-year-old female neutered Ragdoll was presented for signs consistent with extrahepatic biliary tract obstruction (EHBO), including jaundice, hyporexia and lethargy. Marked progressive hyperbilirubinemia and mild anaemia were also present. Abdominal ultrasonography suggested a duodenal mass and pancreatitis as the cause of EHBO. Cytopathological results from fine needle aspirates detected mast cells and eosinophils in the duodenal mass and eosinophils in the spleen and the liver, suggestive of a possible mast cell tumour. A cholecystojejunostomy and a duodenotomy were performed to divert the biliary outflow and obtain biopsy samples, respectively. Eosinophilic sclerosing fibroplasia in the duodenal mass and fungal elements in an abdominal lymph node were reported on histopathological examination. A pan-fungal PCR targeting ITS2 performed on DNA extracted from an abdominal lymph node detected Candida albicans. This report adds to the growing body of evidence that FGESF can occur in association with fungal infections.

Radiographic changes of the proximal third metatarsal bone do not predict presence or severity of proximal suspensory desmopathy in a predominately Quarter Horse population.

BACKGROUND: Comparison of radiography to magnetic resonance imaging (MRI) can help objectively assess the value and limitations of radiographs in orthopaedic disease processes. The tarsus and proximal suspensory origin of the metatarsus are commonly imaged regions for lameness. The knowledge gained by comparison between imaging modalities will aid in improving accuracy of radiographic interpretation. OBJECTIVE: To compare the radiographic and MRI findings of the proximal third metatarsal bone (MTIII) and proximal suspensory ligament using MRI as the gold standard. STUDY DESIGN: Retrospective observational study. METHODS: Single hindlimbs of 35 horses with radiographic and high-field (3Tesla (3T)) MRI studies were blindly evaluated by two board-certified veterinary radiologists and a radiology resident. Severity and location of the following parameters were assessed: radiographic MTIII sclerosis and lucent regions, MRI endosteal metatarsal sclerosis and bone marrow lesions, plantar cortical proliferation and resorption, and proximal suspensory desmopathy (PSD). RESULTS: Radiographic osseous changes of MTIII were identified in 54% of limbs, whereas 40% limbs had osseous changes on MRI: 43% of limbs had PSD on MRI. No significant association was found between the presence of radiographic changes in MTIII and PSD on MRI (P = .7). A statistically significant association and positive correlation was found between the severity of radiographic changes and MTIII plantar cortical proliferation and resorption on MRI (P = .01). MAIN LIMITATIONS: Retrospective study with no histopathology. Ability to correlate findings with lameness was limited by the lack of standardised time intervals between onset of lameness, diagnostic analgesia and advanced imaging. CONCLUSION: Radiographic bony changes of proximal MTIII do not reliably predict presence or severity of PSD but are associated with osseous changes at the proximal MTIII. The presence of radiographic changes should warrant additional diagnostics in the region prior to making conclusions about the presence or absence of PSD.

INTRODUCTION/CONTEXTE: La comparaison de la radiographie avec l'imagerie par résonance magnétique (IRM) peut assister dans l'évaluation objective de la valeur et des limites des radiographies pour les processus pathologiques orthopédiques. OBJECTIFS: Comparer les trouvailles radiographiques et d'IRM du métatarsien principal proximal (MTIII) et de la portion proximale du ligament suspenseur du boulet, en utilisant l'IRM comme référence. TYPE D'ÉTUDE: Étude de observationnelle rétrospective. MÉTHODES: Les images radiographiques et d'IRM à haut champ (3 Tesla (3T)) d'un seul membre postérieur chez 35 chevaux ont été évalués à l'aveugle par deux radiologistes vétérinaires diplômés et un résident en radiologie. La sévérité et localisation des paramètres suivants ont été documentés : sclérose et régions lytiques radiographiques du MTIII, sclérose métatarsienne de l'endostéum à l'IRM et lésions de la moelle osseuse, prolifération et résorption plantaire corticale et desmopathie du ligament suspenseur du boulet (DLSB). RÉSULTATS: Des changements radiographiques osseux du MTIII ont été identifiés sur 54 % des membres contre 40% des membres ayant des changements osseux à l'IRM. 43% des membres avaient une DLSB à l'IRM. Aucune association significative n'a pu être identifiée entre la présence de changements radiographiques du MTIII et DLSB à l'IRM (P = 0.7). Une association statistiquement significative et une corrélation positive a été identifiée entre la sévérité des changements radiographiques et la résorption/prolifération plantaires corticales du MTIII à l'IRM (P = 0.01). LIMITES PRINCIPALES: Étude rétrospective sans histopathologie. La possibilité de corréler les données de l'examen de boiterie a été limitée par le manque d'intervalle de temps standardisés entre l'apparition de la boiterie, l'analgésie diagnostique et l'imagerie avancée. CONCLUSIONS: Ces trouvailles démontrent que les changements osseux radiographiques du MTIII proximal ne peuvent prédirent de façon fiable la présence ni la sévérité de DLSB, mais ils sont par contre associés aux changements osseux du MTIII proximal à l'IRM. La présence de changements radiographiques justifie l'utilisation de méthodes diagnostiques additionnelles du MTIII proximal avant de conclure sur la présence ou l'absence de DLSB.

Radiographic evidence of metaphyseal sclerosis secondary to canine distemper virus: 4 cases in juvenile dogs.

BACKGROUND: Metaphyseal sclerosis secondary to canine distemper virus has been described histopathologically, but its radiographic appearance has not been described. OBJECTIVES: Describe the radiographic appearance of metaphyseal sclerosis secondary to canine distemper virus in juvenile dogs as distinct from metaphyseal osteopathy (formerly called hypertrophic osteodystrophy). ANIMALS: Four dogs (2 intact females and 2 intact males) between 2.5 and 4 months of age presented to 2 different veterinary teaching hospitals. METHODS: Retrospective case series in which definitive diagnosis of canine distemper virus based on antemortem positive reverse transcription-polymerase chain reaction (RT-PCR) result or necropsy was required. RESULTS: All 4 dogs were presented for evaluation of neurologic abnormalities, respiratory signs, and lethargy; 2 dogs had gastrointestinal signs and ocular abnormalities. Radiographs on all patients featured multifocal, symmetric, metaphyseal sclerosis, with no evidence of lysis or changes to the adjacent growth plate. The metaphyseal sclerosis was most apparent at the proximal humeral diaphyses and other included long bones. Diagnosis of distemper was confirmed by necropsy (2 of 4 dogs) or positive RT-PCR results (2 of 4 dogs). Three dogs were euthanized because of progressive illness, and 1 dog was lost to follow-up. CONCLUSION AND CLINICAL IMPORTANCE: Identification of metaphyseal sclerosis on radiographs during diagnostic evaluation of young dogs should lead to a clinical suspicion of canine distemper virus infection. Sclerosis identified secondary to canine distemper virus is distinct from the necrosis and inflammation of metaphyseal osteopathy.

Computed Tomographic Features of Non-Lame French Bulldog Elbows.

OBJECTIVE: French Bulldogs are predisposed to humeral condylar fractures. Computed tomography (CT) in English Springer Spaniel elbows has allowed identification of humeral intracondylar fissures (HIF), which can cause lameness and predispose to condylar fractures. This study aimed to evaluate CT characteristics of non-lame French Bulldog elbows, to determine the presence of underlying elbow disease. STUDY DESIGN: Retrospective evaluation of CT images from elbows of non-lame French Bulldogs from scans obtained for soft tissue or neurological evaluation was performed. Images were evaluated for the presence of HIF and other elbow abnormalities: condylar and supracondylar remodelling, humeral condylar sclerosis, elbow incongruency, medial coronoid process disease and elbow osteoarthritis. Descriptive statistics were performed. RESULTS: Computed tomographic scans from 37 dogs (74 elbows) were reviewed. No HIF were identified, although 28/74 elbows had an intracondylar sclerotic band. Medial coronoid process disease was noted in 16/74 elbows, and small osteophytes were present in 21/74 elbows, suggesting a degree of subclinical elbow disease. Widening of the caudolateral aspect of the radial incisure was identified (37/74) as a breed normal. Elbow incongruency was otherwise rare. CONCLUSION: Non-lame French Bulldogs showed a low prevalence of occult elbow disease but a proportion had radial incisure widening. Although humeral intracondylar sclerosis was present in over a third of dogs, no HIF were identified and therefore no clear cause for their increased risk of humeral condylar fracture was identified.

A case of feline temporal lobe epilepsy with hippocampal sclerosis and dentate gyrus malformation.

A two-months-old, male, mixed breed cat presented with epileptic seizures. The cat was diagnosed with drug-resistant epilepsy, and died at 3-years of age. No gross lesion was found at necropsy. Histopathologically, the dentate gyrus granule cell layer of the hippocampus was irregularly arranged. Granule cells were dispersed and ectopic cells were sporadically observed in the molecular layer. The granule cells had an enlarged cytoplasm and swollen nucleus. Immunohistochemistry for NeuN and GFAP confirmed severe neuronal loss and mild gliosis in CA1. Binucleation and ischemic change were observed in the remaining pyramidal cells. This report describes a case of feline temporal lobe epilepsy and hippocampal sclerosis associated with dentate gyrus malformation.

Measurement of ulnar subtrochlear sclerosis using a percentage scale in labrador retrievers with minimal radiographic signs of periarticular osteophytosis.

OBJECTIVE: To report the development of a measurement method for quantifying ulnar subtrochlear sclerosis (STS) in Labrador Retrievers. STUDY DESIGN: Prospective blinded study. SAMPLE POPULATION: Radiographs of Labrador Retrievers elbows (n=30) with minimal radiographic signs of periarticular osteophytosis. METHOD: Measurement of STS as a % of the distance between 2 standardized radiographic landmarks (%STS) was developed. Mediolateral radiographic projections of flexed elbows were collected from 2 cohorts termed diseased (n=15; confirmed disease of the medial coronoid process) and control (n=15; free from clinically evident disease). Five observers blindly assessed each radiograph for radiographic technique, elbow positioning, periarticular osteophytosis, and STS, which, if present, was measured and assigned a %STS score. Intraobserver and interobserver variations in measuring STS and the ability to differentiate study cohorts were assessed using receiver operator curve (ROC) characteristics. A P-value of <.05 was considered significant. RESULTS: Median %STS for diseased elbows was 47% (range, 0-74%) and 0% (range, 0-62%) for control elbows. Correlations were not significantly different between each observer's assessments of %STS, with a median Spearman's P-value of .75 (range, .67-.86). All observers differentiated the 2 cohorts with "fair-good" accuracy, with a median ROC value of 0.81 (range, 0.75-0.88). CONCLUSION: Measurement of %STS in Labrador Retrievers was repeatable for each observer and repeatable between observers. CLINICAL RELEVANCE: A method for measuring STS allows comparison of Labrador Retrievers of different sizes, is easy to perform, and could be used to investigate the clinical significance of STS in this breed.

Radiographic analysis of trochlear notch sclerosis in the diagnosis of osteoarthritis secondary to medial coronoid disease.

Trochlear notch sclerosis (TNS) as assessed by radiography has been shown to be increased in elbow dysplasia (ED) associated medial coronoid process disease (MCD). The aims of this study were to investigate whether two defined radiographic tests evaluating TNS would increase the sensitivity of detecting osteoarthritis secondary to MCD, and to assess whether there was a correlation between increasing TNS with severity of MCD. Sixty-one dogs with MCD (121 elbows) were selected from the imaging database. The controls were nine cadavers (18 disease-free elbows). Standard International Elbow Working Group radiographs and CT scans were taken of each elbow. Plain radiographs were analysed using various assessments: osteophyte grade (0-3), coronoid grade (0-3), TNS descriptive grade (0-3) and TNS ratio. The TNS ratio was calculated from the depth of ulnar sclerosis at the level of the disto-cranial margin of the humeral condyles divided by the cranio-caudal ulna depth. The TNS descriptive assessment and ratio both increased the overall sensitivity of diagnosing osteoarthritis secondary to MCD above the other radiographic tests. The sensitivity of the TNS ratio at <0.3 mm was 91%-96% and the TNS descriptive assessment was 77%-96%. Radiographic TNS significantly increased with increasing severity of coronoid disease grade as evaluated by CT p < 0.01. The finding that TNS increases the sensitivity of diagnosing osteoarthritis secondary to MCD is valuable to those that have neither a CT scanner nor arthroscopy readily available. The assessments described in this study are easy to apply and do not require any sophisticated technology in order to detect sclerosis.

[Suspected hippocampal sclerosis in an european shorthair cat diagnosed with polycythemia vera]. / Verdacht auf Hippocampussklerose bei einer Europäisch-Kurzhaar-Katze mit der Diagnose Polycythaemia vera.

A 7-year-old male castrated cat was presented because of an acute onset of lethargy and vestibular ataxia. The cat was diagnosed with polycythemia vera. Later the patient developed additional clinical signs including orofacial twitching, aggressivity, hypersalivation, circling and a head tilt. A magnetic resonance imaging was performed and revealed hippocampal alterations compatible with hippocampal sclerosis. The presented case report describes the clinical signs and hematologic findings in a cat with polycythemia vera and the response of treatment. Another part is the discussion about the hypothesis that the hippocampal alterations were due to a cerebral hypoperfusion caused by the polycythemic condition.

Effects of exercise on chondrocyte viability and subchondral bone sclerosis in the distal third metacarpal and metatarsal bones of young horses.

The objective was to determine the effects of early exercise on the articular cartilage and subchondral bone at specific sites of the distal third metacarpal and metatarsal bones of 12 young Thoroughbred horses allowed free choice exercise at pasture. Six of the horses had additional controlled exercise 5 days per week from mean age of 21+/-20 days of age (range: 3-83 days) until 17.1 months of age. Confocal laser scanning microscopy was used to quantify viable and non-viable chondrocytes. Proteoglycan scoring and modified Mankin scoring was performed and subchondral bone mineral density measured by computed tomography. The number of viable chondrocytes was significantly greater in the conditioned group, which also had a higher Safranin O/Fast Green (SOFG) score than did the group which could exercise only at pasture. There was no difference in mean bone mineral density between groups, nor was there relationship between subchondral bone mineral density and chondrocyte viability. The apparent beneficial effects of early conditioning exercise may support the use of exercise to optimise development of articular cartilage in young individuals.

Reliability of radiological assessment of ulnar trochlear notch sclerosis in dysplastic canine elbows.

OBJECTIVES: The objectives of this study were to quantify the sensitivity and specificity of visual assessment of radiographs of the canine elbow in detecting ulnar trochlear notch sclerosis, to establish interobserver and intra-observer variation for the presence and grade of sclerosis and to quantify the effect of radiographic exposure on observer grading. METHODS: Mediolateral elbow radiographs were obtained from Labrador retrievers (n=34) aged between six and 18 months. Radiographs from dogs with an arthroscopic diagnosis of fragmented medial coronoid process (n=17) and those from a control population (n=17) were subjected to observer grading for the presence or absence of and the grade of ulnar trochlear notch sclerosis. Interobserver and intra-observer variation and observer sensitivity and specificity were calculated. Digital data from the ulnar trochlear notch were correlated with mean observer grade to quantify the effect of radiographic exposure on observer grade. RESULTS: Interobserver agreement was "fair" (kappa=0.251 to 0.369) and intra-observer agreement was "moderate" to "substantial" (kappa=0.462 to 0.667). The sensitivity of observer assessment was 72 per cent with a specificity of 22 per cent. Mean observer grade was not significantly correlated with the degree of radiographic exposure (P=0.70). CLINICAL SIGNIFICANCE: Ulnar trochlear notch sclerosis is a phenomenon associated with fragmented medial coronoid process. However, interobserver agreement in grading this feature is only fair, being identified by observers with moderate sensitivity but with relatively poor specificity. This low specificity may predispose to overdiagnosis in clinical cases. Intra-observer agreement is moderate to substantial, suggesting that individuals can reliably quantify this radiological feature on multiple occasions. The ability of observers to assess the degree of sclerotic change is not significantly affected by radiographic exposure.

Digital analysis of ulnar trochlear notch sclerosis in Labrador retrievers.

OBJECTIVES: To compare ulnar trochlear notch bone radiopacity in Labrador retrievers with and without fragmented medial coronoid process using quantitative analysis of film density on digitised radiographs. METHODS: Mediolateral view elbow radiographs from Labrador retrievers (n=34) aged between six and 18 months were obtained and digitised. Images from dogs with an arthroscopic diagnosis of fragmentation of the medial coronoid process (n=17) were compared with that of a control population (n=17), and this data subject to statistical analysis. RESULTS: A statistically significant relationship between the presence of increased trochlear notch radiopacity and a fragmented medial coronoid process was identified. Fractional analysis of this area shows the region of greatest difference in radiopacity between normal and fragmented medial coronoid process cohorts to be in the trochlear region of the medial coronoid process of the ulna. A decrease in radiopacity values in the dysplastic group versus the normal cohort was observed for the region of the proximo-caudal ulnar trochlear notch. CLINICAL SIGNIFICANCE: An increase in ulnar trochlear notch radiopacity is a finding associated with fragmentation of the medial coronoid process in Labrador retrievers.

Clinical findings, diagnosis, prevalence and predisposing factors for lameness localised to the middle carpal joint in young Standardbred racehorses.

REASONS FOR PERFORMING STUDY: Lameness related to the middle carpal joint (MCJ) occurs in up to 30% of young Standardbred horses in race training and the incidence increase with radiographic severity of third carpal bone (C3) sclerosis on DPr-DDIO (skyline) view of the carpus. Factors predisposing horses to carpal injury have not been well investigated. OBJECTIVES: To determine the importance of MCJ lameness as a cause of wastage in young Standardbred racehorses, stage of training at which it occurs and predisposing factors, and to describe clinical findings and diagnosis. METHODS: Standardbred horses (n = 114) entering their first year of race training were examined at approximately 3-month intervals over 12-18 months. For 87 of the horses, a training diary was available and these horses were trained at 3 different stables, each using a different exercise regime. At each examination, forelimb conformation, MCJ effusion, MCJ lameness and radiographic findings were graded, and training history and reasons for lost training days recorded. Nuclear scintigraphy and exploratory arthroscopy were performed on a limited selection of horses. Results for horses that developed MCJ lameness during the study period were compared statistically with results for horses that did not. RESULTS: Carpal lameness occurred in 28% of horses and was present in 56% with forelimb lameness. In most cases lameness was mild, bilateral and with little or no MCJ effusion and was attributed to subchondral bone pain associated with radiographic evidence of C3 sclerosis. Carpal lameness was the most common reason for >1 month's rest during the study period. It occurred at any stage of training but, in most cases, some speed training had begun. Of the variables studied, poor forelimb conformation and more intense speed training were predisposing factors. CONCLUSIONS AND POTENTIAL RELEVANCE: The information gained should assist in making recommendations regarding training young Standardbreds to reduce the incidence of MCJ lameness. However, further investigations to determine the optimal training regime are warranted.